When cultivating plants, the plants are e.g. cultivated in greenhouses having transparent walls and roofs. Plants are placed in e.g. troughs on the greenhouse floors which troughs are removed from the greenhouse when the plants are ready for shipping to e.g. customers. In order to simplify the transport of the troughs it is known to use conveying systems in the greenhouses.
A conveying system for conveying of plants is shown in EP 1 407 987 A1.
A device for assisting the growth of plants is shown in GB 922 293, where the device comprises a tower structure occupying little space where containers are fed in at an inlet at the top of the structure, and transported along guiding means to an outlet at the bottom of the structure, where the guiding means is a track arranged spirally within the structure around a central pillar. An elevator is provided for feeding the containers to the inlet.
A problem with conveying systems of the above mentioned kind is that they require a relatively powerful motor as they move all the troughs at the same time.